title: Coupled photonic crystal micro-cavities with ultra-low threshold power for stimulated Raman scattering.
abstract: We propose coupled cavities to realize a strong enhancement of the Raman scattering. Five sub cavities are embedded in the photonic crystals. Simulations through finite-difference time-domain (FDTD) method demonstrate that one cavity, which is used to propagate the pump beam at the optical-communication wavelength, has a Q factor as high as  1.254×10⁸ and modal volume as small as 0.03 μm3 (0.3192(λ/n)3). These parameters result in ultra-small threshold lasing power~17.7 nW and 2.58 nW for Stokes and anti-Stokes respectively. The cavities are designed to support the required Stokes and anti-Stokes modal spacing in silicon. The proposed structure has the potential for sensor devices, especially for biological and medical diagnoses.
authors.affiliation: Photonics Laboratory, Department of Electrical & Computer Engineering, Old Dominion University, Norfolk, VA 23529, USA.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Liu
authors.forename: Zhengbiao
authors.initials: Z
authors.lastname: Ouyang
authors.forename: Sacharia
authors.initials: S
authors.lastname: Albin
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008904:Miniaturization; D008962:Models, Theoretical; D017785:Photons; D012031:Refractometry / Q000295:instrumentation*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*